Opal Tower residents heard cracking noises coming from the building, leading to its Christmas Eve evacuation.

How much confidence can buyers of new apartments have now?

We need to hope the Opal situation is a one-off. The Sydney site where it is built used to be a wetland. It could be a special case.

If new apartments can be deemed too dangerous to live in, banks may get nervous about financing apartment purchases. That could spread price falls from more expensive houses - where it has been mostly focused so far - onto units as well.

The more widespread the dwelling price falls, the bigger the impact on the consumer economy.

We already have plenty of reasons to spend less. We have to hope the economy comes up with reasons that convince us to spend more.